Properties of LiMnBO3 glasses and nanostructured glass-ceramics

• Published in: Solid state ionics 2019-06, Vol.334, p.88-94
• Main Authors: Michalski, Przemysław P., Gołębiewska, Agata, Trébosc, Julien, Lafon, Olivier, Pietrzak, Tomasz K., Ryl, Jacek, Nowiński, Jan L., Wasiucionek, Marek, Garbarczyk, Jerzy E.
• Format: Article
• Language: English
• Subjects: Batteries; Catalysis; Ceramics; Chemical composition; Chemical Sciences; Conductivity; Conductivity enhancement; Crystal structure; Electric properties; Electrical properties; Electrical resistivity; Electrode materials; Electron transport; Glass; Glass ceramics; Grain boundaries; Li-ion cathode materials; Li2O–MnO–B2O3 glasses; Lithium; Lithium-ion batteries; Manganese; Nanocrystals; Nanomaterials; Nanostructure; NMR; Nuclear magnetic resonance; Organic chemistry; Rechargeable batteries; Thermal nanocrystallization
• ISSN: 0167-2738; 1872-7689
• DOI: 10.1016/j.ssi.2019.02.006

Polycrystalline LiMnBO3 is a promising cathode material for Li-ion batteries. In this work, we investigated the thermal, structural and electrical properties of glassy and nanocrystallized materials having the same chemical composition. The original glass was obtained via a standard melt-quenching method. SEM and 7Li solid-state NMR indicate that it contains a mixture of two distinct glassy phases. The results suggest that the electrical conductivity of the glass is dominated by the ionic one. The dc conductivity of initial glass was estimated to be in the order of 10−18 S·cm−1 at room temperature. The thermal nanocrystallization of the glass produces a nanostructured glass-ceramics containing MnBO3 and LiMnBO3 phases. The electric conductivity of this glass-ceramics is increased by 6 orders of magnitude, compared to the starting material at room temperature. Compared to other manganese and borate containing glasses reported in the literature, the conductivity of the nanostructured glass ceramics is higher than that of the previously reported glassy materials. Such improved conductivity stems from the facilitated electronic transport along the grain boundaries. •Glass of nominal composition LiMnBO3 was prepared and characterized.•Glass-ceramics containing MnBO3/LiMnBO3 phases were obtained after heat treatment.•Grain sizes in glass-ceramics were ca. 40–60 nm.•The conductivity of glass-ceramics exceeded 10−12 S·cm−1 at RT.•1D 7Li NMR suggest the presence of two lithium environments in glass.